26 Feb 1941HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) and HrMs O 23 (Lt.Cdr. G.B.M. van Erkel, RNN) both make a short call at Holyhead. They depart from again after a few hours for their passage to Gibraltar. (3)

27 Feb 1941 (position 51.37, -5.28)Late in the afternoon, off Milford Haven near position 51°37'N, 05°28'W HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) and HrMs O 23 (Lt.Cdr. G.B.M. van Erkel, RNN) and their escort the Free French minesweeper FFS La Moqueuse encounter the British merchant Losada (6520 GRT, built 1921). As La Moqueuse was more than a mile behind both submarines the crew of the Losada think they were German U-boats and opened fire. To prevent being hit both submarines crash dive. The crew of La Moqueuse had not seen both submarines dive and was now also under the impression that a German U-boat was nearby and dropped three depth charges. O 21 was the target of the attack but sustains no damage. Both submarines surfaced shortly afterwards. (3)

4 Mar 1941HrMs O 21 (Lt.Cdr. J.F. van Dulm) does not sight her escort at the rendez vouz. The British corvette HMS La Malouine (Lt.Cdr.(Retd.) R.W. Keymer, RN) was supposed to meet her and escort her to convoy OG 54. O 21 now proceeded along the expected path of the convoy independently. (3)

1451 hours - Sighted mast. Started attack. The convoy was later seen to be made up of five merchant vessels of 4000 to 5000 tons each and two Lampo class destroyers as escort.

1515 hours - Heard the HE of what was thought to be a third destroyer.

1553 hours - Fired four torpedoes from 4500 yards at two of the merchant ships. Seven minutes after firing a double explosion was heard. O 21 went to a depth of 35 meters and retired to the South-West upon firing so the results were not observed.

1609 to 1701 hours - 24 Depth charges were dropped by two of the destroyers. O 21 went to 87 meters.

1715 hours - Heard the last HE fade out. Returned to 40 meters.

2130 hours - Surfaced. Nothing in sight.

The convoy attacked had left Tripoli on 27 July and arrived at Naples on 30 July and was made up of the Italian merchants Ernesto (7399 GRT, built 1914), Nita (6803 GRT, built 1913), Nirvo (5270 GRT, built 1919), Aquitania (4971 GRT, built 1924), Palmaiola (1961 GRT, built 1918) and tanker Castelverde (6958 GRT, built 1921). Escorts were Italian destroyers Folgore, Saetta, Fulmine and (possibly) torpedo boat Giuseppe Sirtori. (9)

3 Aug 1941 (position 38.47, 9.21)HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) attacked and damaged an Italian barquentine with gunfire South-East of Cagliari, Sardinia, Italy near position 38°47'N, 09°21'E. A torpedo was fired first but it ran under so O 21 surfaced and engaged with gunfire.

The target was the auxiliary schooner V 164 / Maria Teresa (219 GRT, built 1913) on night patrol off Cagliari. There was no resistance as it was only armed with two 8mm machine guns. After making an SOS, the crew of fourteen took to the lifeboats. Marina Cagliari dispatched two auxiliary minesweepers and one found the two lifeboats at dawn, there had been no casualties. The abandoned Maria Teresa was located drifting in position 38°28.5'N, 10°31.5'E (this position appears too far east and is probably a typographical error and should most likely be 09°31.5'E) and the tug Cereo towed her back to Cagliari. She was found undamaged (despite van Dulm’s claims) and immediately resumed service.

1913 hours - Fired one torpedo from 1500 yards. It ran under her stern.
Surfaced and engaged the target with gunfire. Range 1200 to 1500 yards. 25 Rounds were fired for at least seven hits, five in the engine room and two on the forecastle. Broke off the action at 2045 hours owning to the darkness fearing that MAS boats were also in the area and could attack O 21 unobserved. (9)

0618 hours - Fired bow tubes 1 and 3 from 2200 yards. No hits were obtained. It was intended to fire four torpedoes but O 21 lost depth control during the attack.

0625 hours - Heard one explosion. HE ceased.

0635 hours - HE was heard again. Started reloading tube 1 and 3.

According to Italian sources submarine Emo was returning home after operating in the Atlantic, she witnessed a torpedo track passing 1000 meters astern followed by an explosion. (9)

1 Sep 1941 (position 39.19, 13.21)HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) sighted a convoy of three merchant ships about 40 nautical miles North of Isola di Ustica, Italy in position 39°19'N, 13°21'E. As the ships turned out to be Vichy French they were not attacked.

(All times are zone -1)
1518 hours - Sighted three big ships right ahead, distance 7 nautical miles. Started attack. Two of the ships were later seen to have three funnels, the other ship had two funnels.

1618 hours - Ended attack on convoy as the ships were seen to be Vichy French. The ships are thought to be the following vessels:
D'Artagnan (passenger / cargo ship, 15105 GRT, built 1925)
Champollion (passenger ship, 12263 GRT, built 1925)
Massilia (passenger / cargo (reefer) ship, 15147 GRT, built 1920).
They appeared to be heading towards the Straits of Messina.

Note: D?Artagnan was at Saigon at that time so she could not be one of the ships sighted by O 21. (9)

3 Sep 1941 (position 39.45, 13.32)HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) sighted a convoy of three merchant ships about 60 nautical miles North-North-East of Isola di Ustica, Italy near position 39°45'N, 13°32'E. As the ships turned out to be Vichy French they were not attacked.

(All times are zone -1)
0643 hours - Heard HE bearing 150°.

0715 hours - Sighted smoke bearing 160°. Started attack.

0755 hours - Sighted three ships.

0815 hours - Identified the ships as Vichy-French. Stopped attack. Convoy appeared to come from the Straits of Messina and steering for Strait Bonifacio. (9)

0120 hours - Fired 2 torpedoes on merchant vessel from 900 yards. Both torpedoes hit, one beneath the bridge and one near the after hatch.

0124 hours - Surfaced and picked up 22 survivors. (9)

6 Sep 1941 (position 41.05, 10.20)HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) attacked an Italian convoy with two torpedoes about 50 nautical miles East of La Maddalena near position 41°05'N, 10°20'E. No hits were obtained.

[So far no info on the targets]

(All times are zone -1)
0405 hours - Sighted ship bearing 340°. Later it was seen that it was one of two merchant ships in a convoy that was escorted by an Armed Merchant Cruiser.

0420 hours - Submerged and started attack.

0428 hours - Fired two torpedoes from 700 yards. Went to 35 meters. The rear ship went directly overhead. Returned to periscope depth to try to take a stern shot at this ship but this was not possible. No hits were obtained with the two torpedoes fired. (9)

7 Sep 1941 (position 41.09, 9.54)HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) attacked what was thought to be an Italian minelayer of the Fasana class about 20 nautical miles East of La Maddalena near position 41°09'N, 09°54'E.

The target was probably the minelayer Durazzo (610 tons, built 1927) on her way from Naples to La Maddalena where she arrived at 0845 hours the same morning. Twenty days later Durazzo would lay the minefield that apparently was fatal to the submarine HMS P 311 during operation PRINCIPAL (January 1943).

(All times are zone -1)
0105 hours - Sighted ship bearing 090°.

0118 hours - Submerged but lost target out of sight.

0140 hours - Surfaced, but remained trimmed down.

0150 hours - Sighted target again bearing 210°. Made end around to get ahead of the target.

0420 hours - Submerged. Started attack.

0453 hours - Fired one torpedo from 500 yards. Missed. The target was now thought to be a minelayer of the Fasana class so the torpedo most likely ran under. Retired to the South-East. (9)

8 Sep 1941 (position 38.54, 9.50)While on patrol near Cagliari Bay HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) tries to attack an Italian convoy but fails to do so about 5 nautical miles East of Isola Serpentara near position 39°09'N, 09°43'E.

Later O 21 fired her last remaining torpedo at another Italian convoy about 15 nautical miles South-East of Isola dei Cavoli near position 38°54'N, 09°50'E. The torpedo missed.

[So far no info on the targets]

(All times are zone -1)
1145 hours - Sighted two ships bearing 023°. An Cant. Z501 aircraft was overhead. Started attack. The ships were thought to be an Asmara-type cargo vessel escorted by an armed merchant cruiser type Città di Napoli.

1307 hours - Could not close the distance to less than 4000 yards. Concluded that attack had failed and don't fire the last remaining torpedo. Proceeded Southwards. Ships were later seen to enter Cagliari Bay.

------------------------------------------------

1800 hours - Sighted ship bearing 265°. Distance 7000 yards. Started attack. Soon more ships were sighted. The convoy was made up of an armed merchant cruiser type Città di Napoli (possibly the same ship sighted earlier today), one small tanker (3000 tons) and two merchant vessels (7000 and 4000 tons).

1929 hours - Fired one torpedo (the last) from 1000 yards at the 7000-ton merchant vessel. Missed. Set course to the South-West. (9)

1253 hours - Fired two torpedoes from 900 yards. The first torpedo ran on the surface. The second torpedo hit the ships stern. The ship was seen to sink in three minutes, stern first with the bow rising vertically into the air.

The crew of 30 (including three wounded) were later picked up according to Italian sources. (9)

(All times are zone -1)
1530 hours - Sighted three ships bearing 140°. The convoy consisted of one empty tanker of about 5000 tons and two merchant vessels of about the same size. They were in single line ahead. 1000 Yards on the beam on the port side there was a Lampo-class destroyer. Course of the convoy was 315°, speed 8 knots.

1605 hours - Sighted, at a distance of 500 yards, a torpedo boat of the Abba-class. It was followed by a laden modern tanker of about 5000 tons. O 21 went deep as the Lampo class destroyer hoisted a flag signal and turned towards.
1620 hours - The torpedo boat turned to the North and joined the Northbound convoy.

1626 hours - In position 41°47'N, 12°06'E fired two torpedoes against one of the 5000 tons merchants. O 21 broke surface after venting of the first torpedo tube failed. It was intended to fire a third torpedo but this one was not fired. O 21 dived again and went to 60 meters, later to 40 meters.

1636 hours - The torpedo boat dropped its first depth charges. They were very close.

1656 hours - The torpedo boat dropped its last depth charge and later made off to the North.

According to Italian sources the above mentioned Ninetto G. was in convoy with merchant Valsavoia (5733 GRT, 1919) proceeding to La Spezia escorted by the torpedo-boat Giacinto Carini.
Carini had just been escorting the southbound tanker Iridio Mantovani (10540 GRT, built 1939) and had met the northbound Ninetto G. and Valsavoia escorted by the torpedo-boat Perseo. The two convoys had just exchanged escort. (9)

16 Nov 1941 (position 40.15, 9.45)While on patrol in the Tyrrhenian Sea HrMs O 21 (Lt.Cdr. J.F. van Dulm) attacked the Italian merchant Itu (1578 GRT, built 1895) off the East coast of Sardinia about 7 nautical miles East of Cala Gonone in position 40°15'N, 09°45'E. All torpedoes fired missed their target.

(All times are zone -1)
0727 hours - In position 40°15'N, 09°45'E heard HE and sighted ship bearing 230°. It was a grey dazzle painted merchant vessel of about 3000 tons, course 010°, speed 8 knots, distance 4500 yards. The camouflage of the ship made it very difficult to see against the background. Started attack.

0741 hours - Fired two torpedoes from 2000 yards. As the ship was seen to evade the torpedo tracks these must have been seen. (9)

21 Nov 1941 (position 41.55, 11.27)HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) attacked a liner in a convoy about 15 nautical miles South-West of Civitavecchia, Italy in position 41°55'N, 11°27'E. Two torpedoes were fired but no hits were obtained.

(All times are zone -1)
0645 hours - Heard HE bearing 110°.

0705 hours - Sighted a medium seized merchant vessel on a course of 300°. Started attack.

0710 hours - The ship now proved to be a heavily zigzagging Armed Merchant Cruiser belonging to a convoy of 2 medium seized merchant ships and 1 liner that was escorted by 2 AMC's. General course of the convoy was 045°.

0715 hours - Dived to a greater depth as a Cant Z 501 flying boat passed overhead just after the nearest AMC had hoisted a pendant. Returned to periscope depth shortly afterwards.

0739 hours - Fired two torpedoes at the liner from 1800 yards. Went deep. No hits were obtained.

0810 hours - The convoy was now out of sight.

This liner might have been Citta di Trieste (4785 GRT, built 1915) but as of yet (January 2012) this cannot be confirmed. This will have to be researched further at the Ufficio Storico in Rome, Italy in the future. (9)

(All times are zone -1)
2134 hours - Sighted ship bearing 125°.
The ship proved to be a 2-mast schooner of about 500 tons.

2145 hours - Opened fire with the deck gun. The crew abandoned ship with their small boat after the first round.

2210 hours - The schooner was seen to sink bow first after 47 rounds. (9)

23 Nov 1941 (position 41.56, 10.50)HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) about 25 nautical miles South of Isola del Giglio in position 41°56'N, 10°50'E fires two torpedoes against a contact obtained by HE (Hydrophone Effect) alone. No ship was seen. Both torpedoes failed to hit their unknown target.

(All times are zone -1)
0028 hours - Heard HE bearing 053°.

0205 hours - In position fired two torpedoes from the deck tubes at the very distinct loud HE. The target was not seen. No hits were obtained. (9)

24 Nov 1941 (position 40.56, 10.23)HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) sank an Italian schooner with gunfire off the east coast of Sardinia, Italy about 30 nautical miles South-East of La Maddalena in position 40°56'N, 10°23'E. This was most likely the Nuovo Sant'Antonio (52 GRT) that disappeared without a trace at this time during a trip from Civitavecchia to Arbatax.

O 21 arrived at Gibraltar later on the same day ending her 15th war patrol.

For an eyewitness account on this encounter between these two submarines see this website (offsite link).

(All times are zone -1)
0035 hours - Sighted a suspicious silhouette bearing 085°. Stopped zigzagging and increased speed to 17 knots. It was thought that the dark shape was either a submarine of a motor launch.

0044 hours - The suspicious ship flashed with a dimmed signal lamp.

0048 hours - The contact again flashed the challenge. It was recognised as German by the British signalman. Reduced speed to 15 knots.

0050 hours - Fired both stern tubes in short succession. The first torpedo missed and the enemy turned away just as Lt.Cdr. van Dulm had thought he would do. The first torpedo had no effect as it passed close to the enemy's starboard site. The second one had the desired effect as it hit the U-boat abaft the conning tower and blew the stern off. The U-boat was seen to sink by the stern at an angle of 45°.

0112 hours - O 21 now proceeded to where the enemy sank to collect evidence of this sinking when survivors were noticed in the water. 12 Survivors were picked up including the Commanding Officer.

The Germans had sighted O 21 first but as the silhouette of the Dutch submarine looked like a German U-boat a challenge was made. The quick reaction of Lt.Cdr. van Dulm surprised the Germans. (9)

5 Dec 1941HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) departed from Gibraltar bound for the U.K. where she is to refit.

For the daily positions of HrMs O 21 during the passage to the U.K. see the map below.

16 Dec 1941HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) departed from Holy Loch for her 16th war patrol. Her refit is postponed as every submarine available is to be used to patrol off Brest, France. The British are under the impression that the German heavy ships there are about to sortie into the Atlantic Ocean.

For the daily positions of HrMs O 21 during this patrol see the map below.

24 Dec 1941HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) arrived and ended her 16th war patrol at Milford Haven. It is decided after consulting experts that O 21 is not fit for further patrols due to problems with the electric motors. (3)

12 Oct 1942HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) arrived at Salandha Bay, South Africa. En-route from Pointe Noire O 21 was ordered to proceed to Salandha Bay instead of Simonstown due to the threat of German U-boats that were operating in South African waters at that time. (11)

17 Oct 1942HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) arrived at Simonstown. At Simonstown defective machinery (Vulcan clutch for port main engine) is removed and replaced by a Vulcan clutch from HrMs O 19 (Lt.Cdr. H.F. Bach Kolling, RNN(R) that is also in Simonstown en-route from the Far East to the U.K. to be refitted. (12)

(All times are zone -6.5)
0720 hours - The cargo ship that was sighted yesterday was seen moving around the bay as if to leave Port Blair. Prepared to attack.

0730 hours - The ship was seen to leave the bay. The size of the ship was estimated at 4000 tons.

0750 hours - In position 11°39'N, 92°49'E fired four torpedoes from 1400 yards. Two hits were obtained and the ship sank in five minutes. O 21 retired to the South-East. Two small enemy motor launches left the harbour to hunt the submarine but they were unsuccessful. (3)

11 Apr 1943HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) departed from Colombo for her 18th war patrol (2nd in the Far East). She was ordered to patrol in the Malacca Straits. A special operation is also to be carried out.

For the daily and attack positions of HrMs O 21 during this patrol see the map below.

0511 hours - The target was seen to be a large camouflaged merchant ship of about 7000 tons. The escort was thought to be a Chidori-class torpedo boat. Started attack.

0540 hours - In position 03°26'N, 99°48'E fired four torpedoes from 2000 yards resulting in two hits. One just in front of the bridge and one in hold number 5. The ship broke in two with the front part capsizing and sinking slowly. The aft part burst into flames and sank quickly.

0601 hours - The torpedo boat dropped a pattern of four depth charges but these were not close. O 21 retired to the East-North-East.

0830 hours - The torpedo boat was now lost out of sight.

-----------------------------------------

1110 hours - In position 03°28'N, 100°03'E sighted a ship bearing 090°. Started attack with the deck torpedo tubes but one of the doors could not be opened properly so abandoned this plan and went for an attack with the stern torpedo tubes.

1149 hours - In position 03°23'N, 100°07'E fired two stern torpedoes at the target that was thought to be of about 2000 tons. Range 700 yards. The torpedoes missed. It appeared the target saw the tracks and avoided. She altered course and made for the submarine.

23 Jul 1943HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) departed from Exmouth Gulf for her 20th war patrol. She is to conduct several special operations (under the control of the Dutch NEFIS organisation) off the South coast of Java and Bali and also to the North of Bali and in the Kangean Archipaligo.

The positions of O 21 are 'coded' in the ships log. The ships positions were 'decoded' by us with help of a report in Dutch language on this patrol (No report in English has been found in Dutch or British archives.)

For the daily and attack positions of HrMs O 21 during this patrol see the map below.

27 Jul 1943In the period 27 July to 29 July HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) is to make rendez-vouz off Pulau Sempoe (now Sumbermanjing) with a small sailing vessel carrying an agent. However no sailing vessel displaying the secret markings that were agreed shows up. (15)

2020 hours - Land party no. 2 (3 members of the crew of O 21) to reconnoitre a possible landing area.

2215 hours - The party returned. They had not seen any Japanese.

2245 hours - Party no. 1 and agent '289' were landed.

0100 hours (2nd) - Party no 1 returned. (15)

2 Aug 1943HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) lands a party (party No. 2) to reconnoitre a possible landing place in the Pang Pang Bay. They are back on board after nearly 2 hours.

(All times are (most likely) zone -8)
0550 hours - Dived and returned to the Pang Pang Bay. It was not possible to enter the bay due to the bad visibility.

1600 hours - Enter the bay.

1830 hours - Bottomed in 14.5 meters of water.

1920 hours - Surfaced.

2015 hours - Land party no. 2 to reconnoitre the landing area. Two small fishing vessels are laying on the beach nearby.

2150 hours - Party no. 2 returned. They had seen no Japanese. (15)

3 Aug 1943HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) lands a party (party No. 2) to reconnoitre a possible landing place near the Pang Pang Bay. They are back on board after 1 hour.

Shortly afterwards party No. 1 departed from O 21 in their rubber boat to pick up the agent landed on 1 August. He does not show up and the landing party also don't return to O 21 at the agreed time.

(All times are (most likely) zone -8)
0550 hours - Dived and remain North of the Pang Pang bay.

1200 hours - Entered the bay.

1415 hours - Bottomed at 13 meters inside the bay. Kept periscope watch for a small sailing vessel that showed the agreed markings. None however was seen during the day.

1915 hours - Surfaced.

2000 hours - Landed party no. 2 to check one of the landing areas.

2100 hours - The party returned they had sighted nothing.

2130 hours - Sent landing party no. 1 to the place where the agent was landed two day previously. They were soon lost out of sight in the diminishing visibility.

2145 hours - Signals were sighted on the shore but these could not be read due to the bad visibility. They were thought to be from the landing party. Later it was thought they must have been made by agent '289'.

2300 hours - The signals were still seen on the same place. Signals from O 21 were however not answered. Due to the further diminishing visibility contact was lost around midnight.

0115 hours (4th) - As it was thought that the dinghy of party no. 1 was lost it was decided to sent party no. 2 to look for them.

0400 hours (4th) - Party no. 2 returned. They were unable to find party no. 1.

0410 hours (4th) - O 21 departed the bay.

0546 hours (4th) - Dived. (15)

4 Aug 1943During the afternoon the lost party no. 1 is spotted on a beach in the Pang Pang Bay. Contact was established and after dark they were able to return to the O 21. The agent they were to pick up was however not seen again.

(All times are (most likely) zone -8)
1100 hours - Set course towards the entrance to the bay.

1330 hours - Entered the bay. Sighted party no. 1 on a beach. Signalled with the periscope. Signals were answered. It was agreed that they were to be picked up after dark.

1520 hours - Bottomed in 12 meters of water.

1915 hours - Surfaced and sent party no. 2 to the shore to pick up party no. 1.

2000 hours - Both party's returned to the submarine. During the remainder of the evening O 21 tried to establish contact with agent '289', All attempts were however unsuccessful.

6 Aug 1943In the period 6 August to 8 August HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) is to make rendez-vouz off Goa Goa (now Goa-Daja) with a small sailing vessel carrying an agent. However no sailing vessel displaying the secret markings that were agreed shows up. A small sailing vessel that was thought to show one of the secret markings was stopped on the 7th but as this proved to be a native fishing vessel it was released. (15)

10 Aug 1943In the early morning hours HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) lands party no. 2 on Hertenbeest (Deer) Island, that lays off the North-West coast of Bali. They are to spot aircraft movements during the day.

After dark they were taken off again. They had also shot a deer and brought with them fresh meat for two days. (15)

2015 hours - The ship is lost out of sight, but picked up again shortly afterwards. They had turned towards and were rapidly closing.

2020 hours - The ship signalled and then opens fire with a machine gun.

2022 hours - Dived.

2025 - 2028 hours - Nine depth charges were dropped.

2040 hours - Three more depth charges were dropped.

2400 hours - HE faded out bearing 128°. One hour later O 21 surfaces to find nothing in sight. (15)

13 Aug 1943 (position 7.03, 115.20)During the evening HrMs O 21 (Lt.Cdr. J.F. van Dulm, RNN) is detected and depth charged by a Japanese A/S trawler South of Kangean Island near position 07°03'S, 115°20'E. Minor damage is sustained but O 21 manages to escape on the surface after dark.

(All times are (most likely) zone -8)
1908 hours - Surfaced.

1932 hours - Due to a lightning bolt sighted a ship with two masts and one funnel.

1934 hours - Dived. No HE was picked up.

1950 hours - Nothing could be sighted through the periscope.

1955 hours - Strange noises were picked up on Asdic. Shortly afterwards HE was picked up from a ship crossing shortly ahead from Starboard to Port.